Here are some photos to show how we set up the lap/sash seat-belts in an A roadster on 32 rails. The fiberglass body is a Deuce Customs body.
The belts “pull” from the center, so the drivers belt comes over the left shoulder to the stork at the right hip.
The bench seat is from a Mazda van. I will add photos of the fitted belts and seat later.

Photo 1 shows reinforcement of existing bracing to allow the bracket for the shoulder part of seat belt to bolt to.
It is made from 20mm square tube and 3mm plate.

Photo 2 shows the carrier bracket bolted in place. The carrier bracket is made from 5mm plate.

Photo 3 shows the shoulder seat belt bracket bolted to the carrier.
Provision is made for the shoulder bracket to move from side to side to prevent bunching of the belt.

Photo 4 shows a side view of the shoulder bracket.

Photo 5 shows shoulder belt bracket bolted to the carrier bracket before it is bolted onto the reinforced bracing

Photo 6 shows 3mm reinforcement plate added to existing bracing to allow inertia reel to be bolted in place.

Photo 7 shows the rear view of the carrier bracket (top), and the bracket for the inertia reel, with captive bolts. The inertia reel bracket is made of 3mm plate and fits in from behind the reinforcement plate welded to the existing bracing. The small screw holds the bracket in place.
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